Improvement in burglar-alarms



A. L. LINN. Burglar-Alarm.

No. 202,447. Patented April 16, 187.8.

WITNESSES i'NVENTOR L oYl wt'm .m m,

ATTORN EYS -PETERS, PNOTO-LITHOGRAFHER, WASHINGTON o C UNITED ARTHUR L. LINN, OF CLEVELAND, OHIO.

' IMPROVEMENT IN BURGLAR-ALARMS.

Specification forming part of Letters Patent No. 202,447, dated April 16, 1&78; application filed December 5, 1877.

To all whom it may concern.-

Be it known that I, ARTHUR I). LINN, of Cleveland, in the county of Ouyahoga and State of Ohio, have invented certain new and useful Improvements in Burglar-Alarms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to improvements in burglar-alarms.

In the drawings, Figure l is a plan View of my device with the top plate removed, showing the interior mechanism; Fig. 2, a view of the same with the top plate adjusted and in proper position; Fig. 3, a side elevation of same.

My invention consists in the following parts and' combinations, as hereinafter set forth and claimed, wherein A is arevolving hammer, with a handle, A, projecting outward beyond the rim of the case, and provided, also, with the catch A, for engagement with the trigger, as will hereinafter appear. 13 is a spring of any suitable construction, either a coil-spring, as here shown, or of any other description. Ois a trigger, journaled or hinged into the frame F in such a manner as that when the h'ammerA is thrown back the catch A will have passed the point of said trigger, so that when this trigger is thrown in front it will, by means of the catch A interpose and prevent the return of the hammer A, in the meantime acting against the pressure of the spring B. In this position the device is set, and will remain so until the trigger 0 shall be moved one way or another far enough to disengage itself from the catch A when the hammer will be released and the spring B operate to drive it with great force against the abutment D, which I prefer making a part of the caseF.

A detonating-wafer of fulminate of mercury, or its equivalent, is so placed as to rest against the abutment D when the device is set, and the hammer, when free, striking said wafer, causes it to explode with a loud report. a

F is a cover secured to the casing F by the screw f, said screw answering also the pur-' pose of a pivot to the hammer A. An opening, E, is made in that portion of the case F where the hammer A meets the abutment D. This opening is for the introduction of the detonating-wafer. E is a shieldthat can be placed over the opening E for the purpose of sheltering curtains or the like from injury on account of the explosion of the fulminate.

I do not limit myself precisely \to the construction of the parts herein shown, as my invention consists, essentially, of a rotating hammer, A, driven by a spring, and adapted to be thrown back and held in its set position by any suitable trigger arrangement, and retained there until released by the disturbance of said trigger, and, when released, to be made to explode some detonating substance. This s device is to be secured or nailed to any door or sash, and any suitable auxiliary device may be employed whereby the opening either of the door or sash shall operate to move the trigger O in such a manner as to release the hammer A.

For use in sashes, such a device as shown in Fig. 4 of the drawings, answers a useful purpose. This device is constructed of metal, and may be driven by its point a into the body of the sash, thereby presenting an inclined surface, b, which, byimpin gin g against the trigger O in raising the sash, will operate to release the hammer A.

In this connection, an other use of my device to wit, that of a sash-holdermay be mentioned. This is done by raising the sash until the burglar-alarm is above the device a I). Now, if the trigger be pulled out so as to rest'down upon the said device, its operation in holding the window open is manifest.

For an auxiliary attachment to a door, so that when it is opened an alarm will be given, such a device as shown in Fig. 5 answers an admirable purpose. This is simply a screweye bearin g a ring, (I. WVhen the door is shut this device is in such a position that the ring d may be swung over the trigger G, and when the door is open the ring (I will be retracted, drawing with it the trigger 0, thereby releasing the hammer A.

What I claim is- 1. The combination, with the rotary hammer A A abutment D, and trigger O, of the coiled spring B, one end of which is seated against the case, and the other against thehamrner, substantially as set forth.

2. The combination, with the rotary hammer A A abutmentD, trigger G, and coiled spring B, of the cover F, provided with an opening, E, substantially as set forth.

3. The combination, with the rotary hammer A A, abutment D, trigger G, and coiled spring B, of the cover F, provided with an 0pening,=

E, and the pivoted guard E, substantially as set-forth.

In testimony whereof I have signed my name to this specification in the presence of two F. TOUMEY, W. E. DONNELLY. 

